Holder for metal-boring tools.



E. P-G. GIBBS. HOLDER FOR METAL BORING TOOLS.

APPLIGATION FILED JUNE 9, 1913 1,089,635,, Patented Mar. 10, 191i I SW 514 we mtoz l/qh wwooco LL 11W 000? Y 'Q\. (RWY) S 3 lifi ltllED STATES :fATENT OFFICE.

EDWARD F-Gr. GIBBS, OF WASHINGTON, DISTRICT OF COLUMBIA.

HOLDER FOR METAL-BORING TOOLS insacss.

To all whom it may concern Be it known that I, EDWARD F-G. Glens, a citizen of the United States, residing at Washington, in the District of Columbia, have invented certain new and useful Improvements in Holders for Metal-Boring Tools; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification.

This invention relates to certain new and useful improvements in tool holders and it is designed especially for use upon engine lathes for holding boring tools.

The invention has for its object, among others, the production of a boring bar holder provided with means for raising or lower ing the tool or boring bar so as to secure an exact adjustment and the proper working elevation, having due regard for ri idity, despatch in operation and economy in manufacture.

To these ends and to such others as the invention may pertain, the same consists in the novel construction and in the peculiar arrangement, combination and adaptation of parts, all as will be more fully hereinafter described, shown in the accompanying drawings and then specifically defined in the appended claims.

The invention is illustrated in the accompanying drawings which, with the numerals of reference marked thereon, form a part of this specification and in which Figure 1 is a plan view, the parts being shown as assembled and retaining a boring bar in operative position. Fig. 2 is a plan view of the rectangular base piece. Fig. 8 is a like view of the yoke carrying the horizontal clamping bolt with the vertical king bolt shown in cross section. Fig. 4t is a side elevation of the base piece carrying the vertical king bolt, showing the clamping bolt in cross section, the boring bar and tool lathe seat being shown in vertical section. Fig. 5 is a side elevation of the yoke carrying the horizontal clamping bolt and showing in cross section the boring bar and set screws, and F ig. 6 is an end view of the hollow base ie ce.

Reference now being had to the details of Specification of letters Patent.

Application filed June 9, 1913.

Patented Mar. 10, 1914:. Serial No. 772,686.

the drawings by letters, A designates a shaft which I call a king bolt provided, preferably, at one end with the T-head, a adapted to engage the T-slot of a lathes tool seat 0. It passes through the base piece, which it rigidly holds in working position by means of the screw-threaded nut a B designates the hollow base piece, which has a hole 5 through both the top and bottom walls through which the said vertical kmg bolt passes, an open U-shaped recess, 5 in front end of both side walls through which, and in which, both the boring bar and horizontal clamping bolt pass and move up and down in a radial arc, and tail pieces, Z), projecting backward from both side-walls provided with holes 6*, for the purpose of hinge engagement with the yoke.

C designates a horizontally disposed yoke, iaving two arms, held together by a connecting bridge 0, at the far end and having a iole at the near end of each arm for hinge engagement with the base piece, which it embraces. It has also a suitable horizontally elongated aperture 0 through each arm for the purpose of receiving the boring bar, right and left-hand lugs, 0*, provided with internal screw-threads, and set screws 0", which engage the threads of the said lugs and press against the said bar for the purpose of holding it in fixed position in the said aperture.

D designates the horizontal shaft which I call the clamping bolt, provided at one end with threads or other means of engaging one arm of the yoke, a screw-threaded nut cl, at the other end and a centrally disposed enlarged portion (Z having hole d through which the king bolt A, in this case, passes loosely.

E designates the boring bar carrying the cutter e.

W hen the parts are assembled as shown in Fig. 1, the clamping bolt carried by the yoke passing loosely through the hollow base piece and U-shaped recesses of its side walls, the yoke being hinged as shown and the clamping nut (Z being loose, the bar end of the yoke is free to be raised or lowered to any exact elevation and there locked by tightening the said clamping nut (Z.

It will be seen upon having reference to Fig. of the drawings that the bar holding aperture 0 is bisected through its apex by the horizontal center line of the yoke. Thus,

the center of every bar held therein is intersected by the said line and, as the center of the bar should maintain the same elevation as that of the axial center of the lathe, this obviates the necessity of changing the elevation of the said aperture when changing from a bar of a smaller diameter to larger one. With an aperture elongated vertically, this change in the diameter of the bar involves a change in the elevation of the said aperture equal to half the difierence of the diameters of the said bars. The distance of every change of elevation must be added to the necessary variation in the elevation which adds materially to the size of the tool.

In aboring tool for use on engine lathes, rigidity, the most important feature in a boring tool, demands that the strain on the point of the cutter 6, carried by the boring bar E, should be as near as possible to a line projected from the center of the king bolt, as line a and never beyond a similar line projected from the approximate front end of the lathes tool seat, as line 0 But as boring bars generally work very near the line of the lathe centers, convenience suggests that the bar be advanced beyond the king bolt. Rigidity also demands that the clamping bolt be as near the bar as possible. In other words, the boring bar should be in front of but as near both king bolt and clamping bolt as practicable, consequently by the arrangement shown, by one bolt pass ing through the other, and the clamping bolt through the recesses, l practically cut the axial center of each bolt with the other and obtain the desired result without weakening the bolts by bending or side-slotting either. It is practically immaterial as to which of the two bolts is apertured.

I make the base piece hollow, in order to save the cost of superfluous metal, eliminate unnecessary weight, facilitate manufacture and make internal room for the free movement of the boring bar and enlarged portion of the clamping bolt. 1 recess the front end of the side walls of the base piece in order to bring the axial center of the clamp ing bolt back to the axial center of the king bolt, to make room for the free vertical movement of both it and the boring bar, to extend the bearing of the base piece on the lathes tool seat forward ano to extend the frictional engagement between the yoke and side walls of the base piece up to and around the boring bar. 1 project tail pieces for hinge engagement with the yoke backward from the main base piece, in order to increase the radius of the arc described by the vertical movement up the bar and give the tool a more symmetrical appearance.

What I claim is:

1. As an article of manufacture a hollow base piece of rectangular form for boring bar holders, having four walls rectangular to each other and vertical opposing holes through top and bottom walls, suitable for retaining a king bolt, substantially as set forth.

2. As an article of manufacture a base piece of rectangular form for boring bar holders, having two vertical sides, having also a- U-shaped recess at the front end thereof adapted to receive a central portion of a horizontally disposed shaft and having also a vertical hole suitable for retaining a king bolt, substantially as set forth.

3. As an article of manufacture, a hollow base piece of rectangular form for boring bar holders, having two vertical side walls, provided with recesses in their front ends adapted to receive a horizontally disposed shaft, substantially as set forth.

4t. As an article of manufacture, a hollow base piece of rectangular form for boring bar iolders, having two vertical side walls adapted to receive an embracing yoke, from which walls tail pieces adapted to engage the arms of the said yoke project backward; substantially as set forth.

5. As an article of manufacture, a base piece of rectangular form for boring bar holders, having two vertical sides adapted to receive an embracing yoke, provided with a recess in the front end thereof adapted to receive a horizontally disposed shaft, provided also with a tail piece adapted to en ga e the arm of the said yoke projecting 3a kward; all substantially as set forth.

6. As an article of manufacture, a hollow base niece of rectangular form for boring bar holders having two vertical walls adapted to receive an embracing yoke, having also recesses in the front end thereof adapted to receive a horizontally disposed. shaft, and tail pieces adapted to engage the said yoke projecting backwaro; substantially as set forth.

7. As an article of manufacture a yoke for boring bar holders, having two horizontally disposed arms adapted to embrace in movable engagement therewith a rectangular base piece which has its front end recessed horizontally and having also in each arm a horizontally elongated bar holding aperture which coincide with the recess of the said base piece, substantially as set forth.

8. As an article of manufacture, a yoke for boring bar holders consis of lugs for engaging set screws, a bricge and two arms which said bridge connects, the said arms being provided with suitable horizontally elongated apertures for receiving a boring bar, which is held in operative position by the said set screws, the said arms being also adapted to embrace base piece with hinge engagement at one end and clamp engagement toward the other end for the purpose of raising or lowering the boring bar by radial movement to its proper working elevation; substantially as set forth.

9. In a boring bar holder, the combination of avertical king belt, a hollow rectangi'llar base piece having its front end recessed horizontally and a yoke embracing the said base piece and adapted to hold a boring bar in horizontal working position; all substantially as set forth.

10. In a boring bar holder, the combination of a vertical king bolt, a. base piece having a recess at its front end adapted to receive a horizontally disposed shaft, and a yoke embracing the said base piece with which itis connected and adaptedtoholda boring bar in working position; all substantially as set forth.

11. in a boring bar holder, the combina tion of a vertical. king bolt, a base piece having a tail piece projecting backward with which it is integral, and a yoke embracing the said base piece and movably engaged with the said tail piece; all substantially as set forth.

12. In a boring bar holder, the combination of a vertical king bolt, a hollow base piece provided with recesses at its front end adapted to receive a horizontally disposed shaft, and a yoke embracing the said base piece with which it has hinge connection and adapted to hold a boring bar in working position; all substantially as set forth.

13. In a boring bar holder, the combination of a vertical king bolt, a hollow base piece having tail pieces with which it is integral projecting backward, and a yoke embracing the said base piece and engaging" the said tail pieces and adapted to hold a boring bar in working position; all substantially as set forth.

14-. In a boring bar holder the combination of a vertical king bolt, a base piece having two vertical sides adapted to receive an embracing yoke, having also a recess at its front end adapted to receive a shaft in horizontal position, having also a tail piece with which it is integral adapted to engage a yoke, and a yoke embracing the said base piece, engaging the said tail piece and adapted to hold a boring bar in horizontal position, substantially as set forth.

15. In a boring bar holder the combination of a vertical king bolt, a hollow base piece having two vertical walls with recesses at their front ends adapted to receive a shaft in horizontal position, having also tail pieces with which it is integral projecting backward, and a yoke embracing the said base piece, engaging the said tail piece and adapted to hold a boring bar in horizental working position, substantially as set forth.

16. In a boring bar holder, the combination of a rectangular base piece, and a yoke having two arms connected by an integral bridge and having horizontally elongated apertures ei'nbracing the said base piece to which it is movably engaged and adapted to hold a boring bar in horizontal position; all substantially as set forth.

17. In a boring bar holder, the combination of a base piece having its front end recessed horizontally, with a yoke having lugs engaging set screws, a bridge and two arms which said bridge connects, the said arms being provided with suitable horizontally elongated apertures which coincide with the recess of the said base piece to receive a boring bar which is held in operative positionby the said set screws, thesaidarms also embracing the said base piece with hinge engagement at the near end and clamp engagement toward the other end; all substantially as set forth.

18.111 a boring bar holder, the combination of a base piece, having its front end recessed horizontally, a yoke having two arms provided with horizontally elongated apertures, which coincide with the recess of the said base piece, and which hold a boring bar in working position, the said arms also embracing the said base piece with which they have movable engagement, and a horizontal clamping bolt which clamps the said arms against the sides of the said base piece when the said boring bar is at the proper elevation, substantially as set forth.

19. In a boring bar holder, the combination of a base piece carrying a vertical king belt, a. yoke having two arms provided with means for holding a boring bar in working position, the said arms embracing the said base piece, with which they have hinge engagement, and a horizontal clamping bolt carried by the said arms, the axial center of which is practically out by the axial center of the vertical king bolt, and means through which the body of one bolt passes the body of the other without physical contact.

20. In a boring bar holder, the combination of a base piece carrying a vertical king bolt, a yoke having two arms provided with means for holding a boring bar in working position, the said arms embracing the said base piece with which they have hinge engagement, and a horizontal clamping bolt carried by the said arms which clamps them to the said base piece when the said bar is at the proper elevation, the said clamping bolt having a centrally disposed transverse hole through which the said vertical king bolt passes.

21. In a boring bar holder, the combina tion of a base piece carrying a vertical king bolt and having a horizontally disposed recess at its front end adapted to receive a shaft in horizontal working position and in which it may move up or down in a radial are, a yoke having two arms provided with means for holding a boring bar in working position and embracing the said base piece with which it has hinge engagement, and a horizontal clamping bolt carried by the said arms which clamps them to the said base piece when the said bar is at proper elevation, the said clamping bolt having a centrally disposed transverse hole through which the said vertical king bolt projects; all substantially as set forth.

22. In a boring bar holder, the combination of a hollow base piece carrying a king bolt and having side walls in the front end of which are horizontally disposed recesses adapted to receive a bolt and bar in horizontal working position and in which they may move up or down in a radial are, a

yoke having two arms provided with means for holding a boring bar in working position and embracing the said base piece with which it has hinge engagement, and a horizontal clamping bolt carried by the said arms which clamps them to the base piece when the said bar is at the proper elevation, the said clamping bolt having a centrally disposed transverse hole through which the said vertical king bolt passes; all substantially as set forth.

In testimony whereof I hereunto afiix my signature in presence of two witnesses.

EDWARD F-G. GIBBS. Witnesses:

FRANKLIN H. HOUGI-I, ELsm B. LADD.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Eatents.

Washington, D. G. 

